Wikipedia Article About Brown rice syrup on Wikipedia Brown rice syrup is an extremely versatile and relatively healthy sweetener which is derived by culturing rice with enzymes to break down the starches, then straining off the liquid and cooking it until the desired consistency is reached. The final product is roughly 50% soluble complex carbohydrates, 45% maltose, and 3% glucose. The glucose is absorbed into the bloodstream immediately, the maltose takes up to one and a half hours to be digested, and the complex carbohydrates take from two to three hours, providing a steady supply of energy. Rice syrup has a shelf life of about a year, and once opened, should be stored in a cool, dry place.